Bitter taste receptors

Abstract

The present invention relates to bitter-taste receptors and their role in bitter taste transduction. The invention also relates to assays for screening molecules that modulate, e.g. suppress or block, bitter taste transduction, or enhance bitter taste response.

1. A process for identifying a compound that binds to a polypeptide encoded by a polynucleotide selected from the group consisting of:
 (a) a polynucleotide encoding at least a mature form of a polypeptide having the deduced amino acid sequence as shown in SEQ ID NO: 11; 
 (b) a polynucleotide having a coding sequence, as shown in SEQ ID NO: 12 encoding at least a mature form of the polypeptide having the deduced amino acid sequence as shown in SEQ ID NO:11; and 
 (c) a polynucleotide encoding a derivative of a polypeptide encoded by a polynucleotide of any one of (a) to (b), wherein in said derivative one to twenty amino acid residues are conservatively substituted compared to said polypeptide, and said derivative has bitter substance binding activity when contacted with an agonist selected from the group consisting of saccharin and acesulfame K 
 wherein said process comprises the steps of: 
 (1) contacting said polypeptide or a host cell genetically engineered with said polynucleotide or with a vector containing said polynucleotide with an agonist of bitter taste receptor activity selected from the group consisting of saccharin and acesulfame K; 
 (2) detecting the presence of the compound which binds to said polypeptide; and 
 (3) determining whether the compound binds said polypeptide. 
 
     
     
       2. A process for the production of a food or any precursor material or additive employed in the production of foodstuffs comprising the steps of: identifying a compound according to the process of  claims 1 ; and (2) admixing the identified compound with a foodstuff precursor material or additive employed in the production of foodstuffs. 
     
     
       3. A process for the production of a nutraceutical or pharmaceutical composition comprising the steps of: identifying a compound according to the process of  claims 1 ; and (2) formulating the identified compound with an active agent in a pharmaceutically acceptable form. 
     
     
       4. A process for identifying an antagonist of the bitter taste receptor activity of the polypeptide encoded by a polynucleotide selected from the group consisting of:
 (a) a polynucleotide encoding at least a mature form of the polypeptide having the deduced amino acid sequence as shown in SEQ ID NO: 11; 
 (b) a polynucleotide having a coding sequence, as shown in SEQ ID NO: 12 encoding at least a mature form of the polypeptide having the deduced amino acid sequence as shown in SEQ ID NO:11; and 
 (c) a polynucleotide encoding a derivative of a polypeptide encoded by a polynucleotide of any one of (a) to (b), wherein in said derivative one to twenty amino acid residues are conservatively substituted compared to said polypeptide, and said derivative has bitter taste receptor activity when contacted with an agonist selected from the group consisting of saccharin and acesulfame K comprising: 
 (1) contacting said polypeptide or a host cell genetically engineered with said polynucleotide or with a vector containing said polynucleotide with a potential antagonist; 
 (2) determining whether the potential antagonist antagonizes the bitter taste receptor activity of said polypeptide; and 
 (3) contacting of the polypeptide with an agonist selected from the group consisting of saccharin and acesulfame K. 
 
     
     
       5. The process of  claim 4  in which said contacting with an agonist is carried out prior to, concomitantly with, or after step (1). 
     
     
       6. A process for the production of a food or any precursor material or additive employed in the production of foodstuffs comprising the steps of: (1) identifying an antagonist according to the process of  claims 4 ; and (2) admixing the identified antagonist with a foodstuff precursor material or additive employed in the production of foodstuffs. 
     
     
       7. A process for the production of a nutraceutical or pharmaceutical composition comprising the steps of: (1) identifying an antagonist according to the process of  claims 4 ; and (2) formulating the identified antagonist with an active agent in a pharmaceutically acceptable form.